Conventionally, there has been a heat exchanger formed by dividing perforated fins, which have perforations formed therein, at their perforations. More specifically, this heat exchanger is formed by inserting heat transfer tubes into insertion holes of a perforated fin and then separating the fin at the perforations so that two heat exchangers are formed.
The conventional heat exchanger shown above, in which the fins can be separated at the places of the perforations, is easy to manufacture, having an advantage that heat exchangers of different dimensions can be easily manufactured by separating the fins at the perforations or not separating the fins at the perforations but leaving the perforations as they are.
However, the above conventional heat exchanger, while having an advantage of easiness in changing dimensional settings of the fins, has a problem that because, in division of the fins, burrs are formed on an outer edge of the heat exchanger formed by dividing the perforated fins at the perforations and corresponding to places of the fins where the perforations have been separated, condensed water (dew drop water) generated on the fins during the use of the heat exchanger may scatter from the fins along the burrs. In particular, when the conventional heat exchanger is used as a heat exchanger on the indoor side of an air conditioner, the condensed water may be scattered indoors by air blows, giving rise to a serious problem.
Further, in the conventional heat exchanger, since the edge on which the burrs are present is positioned at an outer edge of the heat exchanger, there is another problem that the appearance of the heat exchanger is impaired.